The present invention relates generally to equipment for removing bulk material from dumps, mixed-bed installations or the like, comprising a bridge which traverses the dump and is movable in the longitudinal direction of the dump, and a withdrawing conveyor, which is carried by and fixed to the bridge and includes two revolving parallel endless roller chains having upper and lower courses which are parallel to the longitudinal direction to the bridge, and material-handling elements secured to said roller chains at spaced apart points.
Bulk materials having widely varying particle sizes may be stored temporarily or for substantial times in mixed-bed installations or other dumps.
Equipment of known types for removing material from such dumps comprises a bridge, which is provided with means for removing material from the dump. Such means may comprise a scraper (German Patent Specification No. 2,155,355) or a bucket tube (German Patent Publication No. 1,756,021) or a frame, which rotates about the bridge and is provided with knife edges spaced along the frame (German Utility Model Specification 7,000,092).
Such equipment is suitable for handling bulk material consisting of relatively hard particles but cannot be used for removing bulk material which is abradable and/or very small in particle size. In the handling of such bulk materials, such as coal, fertilizer or the like, any tumbling of the bulk material must be avoided as far as possible. This requirement is not fulfilled by the equipment of known types. For instance, in the known equipment comprising bucket wheels or bucket tubes the bulk material is raised and subsequently falls down to a lower level. This results in an abrading or undesired disintegration of the particles and even dust may be raised in considerable quantities.
It is an object of this invention to provide equipment for removing material from dumps or mixed-bed installations or the like without adversely affecting such material.